InfiniTec - Henning Krauses Blog

Don't adjust your mind - it's reality that is malfunctioning

FindItems and SyncFolderItems performance

By default, Exchange returns a rather large set of properties with each item during a FindItem or SyncFolderItems request. If the query returns a large set of items, this slows down the entire process: On one hand, Exchange needs to get all properties from the store and secondly, all the data needs to be sent over the wire to the calling application. The calling application can specify which items to fetch for a FindItem or SyncFolderItems request by specifying it in the PropertySet parameter. The default property set looks like this:

   1: var PropertySet = new PropertySet(BasePropertySet.FirstClassProperties)

To request only the property id of the items, use this declaration instead:

   1: var PropertySet = new PropertySet(BasePropertySet.IdOnly)

I’ve measured the FindItems call with the Exchange server at my workplace from home. So the call went over the Internet using a 2 MBit connection (on both sides). The inbox folder of my mailbox currently contains approximately 4500 items and I have repeated the measurement two times for each of the propertysets. When querying only for the id of the items, the entire process took 46 seconds to complete. On the other hand, when querying the default set of properties, the whole process took between 1:37 minutes and 1:41 minutes to complete.

But item id is seldom the only property needed. Luckily, the additional properties can be specified on the property set:

   1: var PropertySet = new PropertySet(BasePropertySet.IdOnly)
   2:                   {
   3:                      ItemSchema.Subject,
   4:                      ItemSchema.DateTimeReceived
   5:                   }

Executing this query on my mailbox, took about 50 seconds to complete. This is a significant improvement of the default property set.

Posted by Henning Krause on Sunday, June 7, 2009 12:56 PM, last modified on Saturday, November 27, 2010 6:35 AM
Permalink | Post RSSRSS comment feed